Dear Reuti,
Thank you for the reply.
In examples directory on the computer c1, command "mpiexec -np 4 hello_c" is correctly executed.
If I run " mpiexec -machinefile hosts hello_c " on computer c1, where hosts contains two line :
" node3
localhost
"
the screen displays as follows:
bash: orted: command not found
--------------------------------------------------------------------------
A daemon (pid 5247) died unexpectedly with status 127 while attempting
to launch so we are aborting.

There may be more information reported by the environment (see above).

This may be because the daemon was unable to find all the needed shared
libraries on the remote node. You may set your LD_LIBRARY_PATH to have the
location of the shared libraries on the remote nodes and this will
automatically be forwarded to the remote nodes.
--------------------------------------------------------------------------
--------------------------------------------------------------------------
mpiexec noticed that the job aborted, but has no info as to the process
that caused that situation.
I dont know whats wrong with it.
Thank you.
Regards,
Meng